ruby-on-rails - 延迟作业 - 未定义的方法 `name' 用于 nil :NilClass

Question

我正在努力解决这个错误。我有一个像这样的 Controller Action :

def import
    InventoryItem.import_list(params[:file], current_vendor.id)
    redirect_to vendors_dashboard_path, notice: "Inventory Imported"
end

我的类方法:

class << self
    def import_list(file, vendor_id)
        vendor = Vendor.find(vendor_id)
        SmarterCSV.process(file.path, 
        {:key_mapping => { vendor.import_preference.brand_symbol => :brand,
        vendor.import_preference.product_symbol => :product,
        vendor.import_preference.price_symbol => :price,
        vendor.import_preference.upc_symbol => :upc}}) do |row|

        params = row.first.merge(:store_id => vendor.stores.first.id)
            inventory_item = InventoryItem.create(params)
        end
    end
    handle_asynchronously :import_list
end

当我尝试执行时，我得到未定义的方法错误。此方法无需调用 handle_asynchronously 即可工作，并且当我将其设为普通的 self.import 类方法时。我在这里做错了什么？

*更新**

服务器错误日志:

Started POST "/inventory_items/import" for 127.0.0.1 at 2014-10-06 09:30:53 -0700
Processing by InventoryItemsController#import as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", "file"=>#<ActionDispatch::Http::UploadedFile:0x000001081d3ab8 @original_filename="Inventory1 - Sheet1.csv", @content_type="text/csv", @headers="Content-Disposition: form-data; name=\"file\"; filename=\"Inventory1 - Sheet1.csv\"\r\nContent-Type: text/csv\r\n", @tempfile=#<Tempfile:/var/folders/6Q/6Qj+aFh4A4orYbGW-nE+++TI/-Tmp-/RackMultipart201406-65416-1dcpxp9>>, "commit"=>"Import"}
  Vendor Load (0.9ms)  SELECT "vendors".* FROM "vendors" WHERE "vendors"."id" = 25 LIMIT 1
Completed 500 Internal Server Error in 99ms

NoMethodError (undefined method `name' for nil:NilClass):
  app/controllers/inventory_items_controller.rb:6:in `import'

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Answer 1

params[:file] 在为delayed_job 保存到数据库时将无法正确编码。不要将 params[:file] 对象作为第一个参数传递，而是传递文件路径:

def import
  InventoryItem.import_list(params[:file].path, current_vendor.id)
  redirect_to vendors_dashboard_path, notice: "Inventory Imported"
end

然后直接在你的worker方法中使用路径:

class << self
  def import_list(path, vendor_id)
    vendor = Vendor.find(vendor_id)
    SmarterCSV.process(path, {:key_mapping => { vendor.import_preference.brand_symbol => :brand, vendor.import_preference.product_symbol => :product, vendor.import_preference.price_symbol => :price, vendor.import_preference.upc_symbol => :upc}}) do |row|
      params = row.first.merge(:store_id => vendor.stores.first.id)
      inventory_item = InventoryItem.create(params)
    end
  end
  handle_asynchronously :import_list
end